Action System #4

Actions in this system have at least the following attributes:

Name (Handlebars template) The name of the action displayed in the action list.
Help message (Handlebars template) The message displayed while the action is selected.
Cost (Script expression): The amount of resources the player must have to use this action. If it evaluates to a numerical value, that value is treated as an amount of energy.
Speed (Script expression): The speed of the action, as described in #3.
Effect (Script block): A block of script, evaluated when the action is used.

When the action list is generated before prompting the player to choose an action, the action's Name, Help Message, Cost, and Speed are evaluated and stored, so that they won't change between the action list being displayed and the action being chosen.

Closed as part of the transition to the new project